I was in London yesterday, and I wanted to travel from Aldgate to Neasden. So I got on the first Circle Line train, and at Moorgate there was a Met train in the bay platform, so I changed onto it. This was at ~16.15. My question is, is this common, or timetabled or rare occurrence?
There's one Sunday Morning reverser ex-Neasden at 07:09 and one late night Circle line train Mon-Sat at Moorgate at 00:02 (ex-Hammersmith,23:28) before running empty to Harrow-on-the-Hill or Neasden on Sundays.